Weft control device for weaving looms



E. c. R. DiEDERlcl-:s 2,281,561 WEFT CONTROL DEVICE FO'R WEAVING 4LOOMS Filed Aug. 2, 1938 1 2 Sheets-Shea?I l May 5, 1942.

May 5, 1942- E. C. R. DIEDERlcHs 2,281,561

WEFT QONTROL DEVICE FOR WEAVING LOOMS Filed Aug. 2, 1938 ZVSheets-Sheet 2 u l l 3, /Q v Patented May 5, 1942 aziatiweer ooNraoL DEVICE Fon WEAWNG OMS Emile vCharles `Robert Diederichs, Bourgoin,

France Appiication August 2, 1938, Serial No. 222,653 In France April 14, 1938 1 Claim.

The operation of the central weft stop motions that are generally used is often inaccurate, and this inaccuracy is for the greater part due to the fact that the position occupied bythe weft at the instant when it is controlled by the weft forkY is very variable and very unstable.

The above defects have already been partially eliminated by setting the weft stop motion a certain amount off centre in one direction or the other, instead of arranging same in the middle of the cloth; better results are thus obtained in one of the directions of passing of the weft, but in the other direction the defective operation subsists and is often even aggravated.

The method of operation according to the invention enables an accurate control to be obtained.

Said method is characterized by the use of two weft stop motions which act through the sheet of warp threads and are arranged near the selvedges. Said weft stop motions operate in turn and each of them controls the weft in one direction only, that which corresponds to the picking of the shuttle towards the other weft stop motion.

Owing to this arrangement, at the instant when the weft thread is controlled by the fork, the latter acts on a thread which cannot escape, since the weft thread is attached to the selvedge and the fork is arranged near said selvedge. etremely accurate operation is thus obtained.

An embodiment of a device according to the invention has been described hereinafter by way of example, and illustrated in the accompanying drawings in which:

Fig. 1 shows a front View of the slay.

Fig. 2 is a transverse section showing the clutch members for the loom.

Fig. 3 is a plan view of the part of the loom which carries the clutch members.

Fig. 4 is a transverse section of the loom showing the actuating means for the weft stop motions.

Fig. 5 is a transverse section of the slay land of one of the weft stop motions.

Each of the two weft stop motions is composed of a plate I forming a frame.

At its upper part, said plate carries two bosses I1 and I2 through which pass set screws 2 on which pivots the spindle 3 carrying the needles 4. A spring 5 tends to make the needles swing in the direction F. A projection 6 is iixed on the spindle 3 below the needles. Said projection can be lifted by a bell crank lever 1 which can swing freely on the pin 8 secured to the frame,

and the arm 'I1 of which carries at its end a roller 9 which rolls on a slope Iii1 of the sector Il] that pivots on a pin II secured to the frame I. A spring I-2 urges the roller 9 into contact with the slope V I til.

The sector Iii carries a n'otch |02 which can be engaged by the projection 6 when the needles 4 are not stopped in their downward movement by the weft.

One of the weft stop motions is actuated by the connecting rod 2U, the lever I3 which is fulcrumed at I4, the connecting rod I5, the lever I6 which is fulcrumed at I'I and the cam I8 which is keyed on the picking shaft I9 of the loom.

The connecting rod I5 passes freely across the spindle 2! and carries a ring 22 which is pressed against the end of the lever I6 by the spring 23, one of the ends of which is attached to a ring 2d xed on the connecting rod I5 and the other end to the arm itl of the lever I6. A spring 253 holds the lever I6 constantly in contact with the cam I8.

The other weft stop motion is actuated in an identical manner by the connecting rod 2l, the lever 2B which is fulcrumed at I4, the connecting rod 29, the lever 3B which is fulcrumed at I7 and the cam 3|.

The two cams I8 and 3| are fixed diametrically opposite each other on the shaft I9.

Each of the levers I3 and 28 is adapted to abut, when the corresponding notch m2 is engaged with the projection 6, against a lever 35 which is xed on the spindle 36 which pivots in the bushes 371 and 3i2 of the support 3l.

On the spindle 35 is fixed a second lever 38 which is adapted to act on the spring 39 for engaging and disengaging the loom clutch. The position of said spring shown in Fig. 3 corresponds to the operation of the loom; when it has fallen to the bottom of the slide d@ it is in the position corresponding to the stoppage.

The device operates in the following manner:

As a rotation of the shaft I9 corresponds to two strokes of the slay, it ensues that at each stroke of the slay, only one of the two sectors I0 rocks, and they each rock in turn. The rocking of one of the sectors IF) causes the corresponding needles d to be raised and lowered. If the needles are stopped in their downward movement by the weft, the sector II) is not stopped by the projection 5 and the levers i3 and 28 do not act on the lever 35. If, on the contrary, the weft is absent, one of the projections 5 engages in the notch |02 of the corresponding sector, stopping the rocking of said sector and of the corresponding lever I3 or 28. This latter abuts against the lever 35 which rocks and, through the instrumentality of the lever 38, unhooks the clutch spring 39 from its notch 40 and stops the loom.

The adjustment is such that when the shuttle passes across the shed in the direction F1, the needles of the right hand mechanism are raised and control the weft which is connected to the right hand selvedge; on the contrary, when the shuttle passes in the direction F2, the left hand mechanism controls the weft which is connected to the left hand selvedge.

The control of each weft thread is thus obtained, but as the needles act on the weft thread very near its end which is connected to the cloth, said weft thread has a very definite position and cannot escape control. Consequently, extremely accurate operation is obtained.

It is quite obvious that the invention is not limited to the details which are described and illustrated and that modifications can be made therein Without for that reason exceeding the scope of the invention. Thus, for example, it would be possible to use weft stop motions of a different type from the one illustrated, and the actuating means could also be different as Well as the action on the clutch device, and instead of being applied to a loom in which a picking of the shuttle occurs alternately in each direction, the device could be applied to a loom in which a plurality of pickings successively occur on the same side; obviously in this latter case, the actuation of each weft stop motion must be in conjunction either with the picking movement of the shuttle, or with the weave mechanism, or with the shuttle box motion, etc.

I claim:

A weft thread controlled stop mechanism for looms including two detector forks one of which is mounted at the right hand side of the loom, the other detector fork being mounted at the left hand side of the loom, said detector forks being mounted for movement from a normal position of rest, through the Warp threads of a fabric being formed on the loom to an operative position into engagement with a weft thread being laid by a shuttle of the loom, and independently operated means for moving each of said detector forks from its position of rest to its `operative position immediately behind a shuttle as the shuttle moves from its respective side of the loom to the opposite side thereof to lay a weft thread, a shaft, means for rotating said shaft, and a pair of diametrically opposed cams carried by said shaft for alternately operating said detector fork operating means.

EMILE CHARLES ROBERT DIEDERICHS. 

